The value of -7 + 24 ÷ (-3)(2) is ____

What is the surface area of the square pyramid

user100 [1]

Answer:

128 feet squared

Step-by-step explanation:

you multiply 4 by 4 to get 16 ,

then you multiply 7 by 4 and get 28,

also multiply 28 by 4 and get 112 ,

finally add 112 and 16 to get 128

6 0

3 years ago

Add me as a friend please and I will give you a brain list

lawyer [7]

Answer:

Ok, and it's 9.35423007

Step-by-step explanation:

5 0

3 years ago

Read 2 more answers

Find the coordinates of the midpoint of a segment with the given endpoints.

Step2247 [10]

Answer:

a. (1,2), b. (1, 0)

Step-by-step explanation:

a.

$\frac{x_1+x_2}{2},\frac{y_1+y_2}{2}\\\text{Substitute the values.}\\\frac{-3+5}{2},\frac{5+(-1)}{2}\\\text{Evaluate the numerators.}\\\frac{2}{2},\frac{4}{2}\\\text{Simplify.}\\1,2\\\text{The midpoint of (-3, 5) and (5, -1) is (1, 2).}$

b.

$\frac{x_1+x_2}{2},\frac{y_1+y_2}{2}\\\text{Substitute the values.}\\\frac{-4+6}{2},\frac{-3+3}{2}\\\text{Evaluate the numerators.}\\\frac{2}{2},\frac{0}{2}\\\text{Simplify.}\\1,0\\\text{The midpoint of (-4, -3) and (6, 3) is (1, 0).}$

3 0

3 years ago

Can I get help with these three please?

Black_prince [1.1K]

1) x=
square root ({15}^{2} - {9}^{2} )
all the others are the same method, just remember
the horizontal line^2 + the vertical line ^2 is equals to the line opposite the right angle^2

8 0

3 years ago

The following observations were made on fracture toughness of a base plate of 18% nickel maraging steel (in ksi √in, given in in

Grace [21]

Answer:

A 90% confidence interval for the standard deviation of the fracture toughness distribution is [4.06, 6.82].

Step-by-step explanation:

We are given the following observations that were made on fracture toughness of a base plate of 18% nickel maraging steel below;

68.6, 71.9, 72.6, 73.1, 73.3, 73.5, 75.5, 75.7, 75.8, 76.1, 76.2, 76.2, 77.0, 77.9, 78.1, 79.6, 79.8, 79.9, 80.1, 82.2, 83.7, 93.4.

Firstly, the pivotal quantity for finding the confidence interval for the standard deviation is given by;

P.Q. = $\frac{(n-1) \times s^{2} }{\sigma^{2} }$ ~ $\chi^{2} __n_-_1$

where, s = sample standard deviation = $\sqrt{\frac{\sum (X - \bar X^{2}) }{n-1} }$ = 5.063

$\sigma$ = population standard deviation

n = sample of observations = 22

Here for constructing a 90% confidence interval we have used One-sample chi-square test statistics.

So, 90% confidence interval for the population standard deviation, $\sigma$ is ;

P(11.59 < $\chi^{2}__2_1$ < 32.67) = 0.90 {As the critical value of chi at 21 degrees

of freedom are 11.59 & 32.67}

P(11.59 < $\frac{(n-1) \times s^{2} }{\sigma^{2} }$ < 32.67) = 0.90

P( $\frac{ 11.59}{(n-1) \times s^{2}}$ < $\frac{1}{\sigma^{2} }$ < $\frac{ 32.67}{(n-1) \times s^{2}}$ ) = 0.90

P( $\frac{(n-1) \times s^{2} }{32.67 }$ < $\sigma^{2}$ < $\frac{(n-1) \times s^{2} }{11.59 }$ ) = 0.90

90% confidence interval for $\sigma^{2}$ = [ $\frac{(n-1) \times s^{2} }{32.67 }$ , $\frac{(n-1) \times s^{2} }{11.59 }$ ]

= [ $\frac{21 \times 5.063^{2} }{32.67 }$ , $\frac{21 \times 5.063^{2} }{11.59 }$ ]

= [16.48 , 46.45]

90% confidence interval for $\sigma$ = [ $\sqrt{16.48}$ , $\sqrt{46.45}$ ]

= [4.06 , 6.82]

Therefore, a 90% confidence interval for the standard deviation of the fracture toughness distribution is [4.06, 6.82].

5 0

3 years ago

The value of -7 + 24 ÷ (-3)(2) is _____.